public function beforeRender()
 {
     $userId = $this->session->read('uid');
     $loggedIn = !empty($userId);
     // ak je prihlaseny iba vtedy ma zmysel kreslit menu a vyber semestra
     if ($loggedIn) {
         $menu = new Menu();
         $periods = new Periods();
         $menuHelper = new MenuHelper();
         $selSemester = $this->session->read('semester');
         $semesterHtml = $menuHelper->renderSemester($periods->getShortAll(), $selSemester, $this->url);
         $menuItems = $menu->getForUser($userId);
         $admin = $this->session->read("admin");
         $adminActing = isset($admin);
         $menuHtml = $menuHelper->render($menuItems, $adminActing);
     } else {
         $menuHtml = $semesterHtml = "";
     }
     $this->addToTemplate("SEMESTER", $semesterHtml);
     $this->addToTemplate("MENU", $menuHtml);
     $helpHtml = "<a target='_BLANK' href='{$this->helpLink}'>Help</a>";
     $this->addToTemplate('HELP', $helpHtml);
 }